localrepo: create new function for instantiating a local repo object
Today, there is a single local repository class - localrepository. Its
__init__ is responsible for loading the .hg/requires file and taking
different actions depending on what is present.
In addition, extensions may define a "reposetup" function that
monkeypatches constructed repository instances, often by implementing
a derived type and changing the __class__ of the repo instance.
Work around alternate storage backends and partial clone has made it
clear to me that shoehorning all this logic into __init__ and operating
on an existing instance is too convoluted. For example, localrepository
assumes revlog storage and swapping in non-revlog storage requires
overriding e.g. file() to return something that isn't a revlog. I've
authored various patches that either:
a) teach various methods (like file()) about different states and
taking the appropriate code path at run-time
b) create methods/attributes/callables used for instantiating things
and populating these in __init__
"a" incurs run-time performance penalties and makes code more
complicated since various functions have a bunch of "if storage is X"
branches.
"b" makes localrepository quickly explode in complexity.
My plan for tackling this problem is to make the local repository type
more dynamic. Instead of a static localrepository class/type that
supports all of the local repository configurations (revlogs vs other,
revlogs with ellipsis, revlog v1 versus revlog v2, etc), we'll
dynamically construct a type providing the implementations that are
needed for the repository on disk, derived from the .hg/requires file
and configuration options. The constructed repository type will be
specialized and methods won't need to be taught about different
implementations nor overloaded.
We may also leverage this functionality for building types that don't
implement all attributes. For example, the "intents" feature allows
commands to declare that they are read only. By dynamically
constructing a repository type, we could return a repository instance
with no attributes related to mutating the repository. This could
include things like a "changelog" property implementation that doesn't
check whether it needs to invalidate the hidden revisions set on every
access.
This commit establishes a function for building a local repository
instance. Future commits will start moving functionality from
localrepository.__init__ to this function. Then we'll start dynamically
changing the returned type depending on options that are present.
This change may seem radical. But it should be fully compatible with
the reposetup() model - at least for now.
Differential Revision: https://phab.mercurial-scm.org/D4563
$ hg init
$ echo "[merge]" >> .hg/hgrc
$ echo "followcopies = 1" >> .hg/hgrc
$ echo foo > a
$ echo foo > a2
$ hg add a a2
$ hg ci -m "start"
$ hg mv a b
$ hg mv a2 b2
$ hg ci -m "rename"
$ hg co 0
2 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ echo blahblah > a
$ echo blahblah > a2
$ hg mv a2 c2
$ hg ci -m "modify"
created new head
$ hg merge -y --debug
searching for copies back to rev 1
unmatched files in local:
c2
unmatched files in other:
b
b2
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'a' -> dst: 'b' *
src: 'a2' -> dst: 'b2' !
src: 'a2' -> dst: 'c2' !
checking for directory renames
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: af1939970a1c, local: 044f8520aeeb+, remote: 85c198ef2f6c
note: possible conflict - a2 was renamed multiple times to:
c2
b2
preserving a for resolve of b
removing a
b2: remote created -> g
getting b2
b: remote moved from a -> m (premerge)
picked tool ':merge' for b (binary False symlink False changedelete False)
merging a and b to b
my b@044f8520aeeb+ other b@85c198ef2f6c ancestor a@af1939970a1c
premerge successful
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg status -AC
M b
a
M b2
R a
C c2
$ cat b
blahblah
$ hg ci -m "merge"
$ hg debugindex b
rev linkrev nodeid p1 p2
0 1 57eacc201a7f 000000000000 000000000000
1 3 4727ba907962 000000000000 57eacc201a7f
$ hg debugrename b
b renamed from a:dd03b83622e78778b403775d0d074b9ac7387a66
This used to trigger a "divergent renames" warning, despite no renames
$ hg cp b b3
$ hg cp b b4
$ hg ci -A -m 'copy b twice'
$ hg up eb92d88a9712
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ hg up
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg rm b3 b4
$ hg ci -m 'clean up a bit of our mess'
We'd rather not warn on divergent renames done in the same changeset (issue2113)
$ hg cp b b3
$ hg mv b b4
$ hg ci -A -m 'divergent renames in same changeset'
$ hg up c761c6948de0
1 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ hg up
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
Check for issue2642
$ hg init t
$ cd t
$ echo c0 > f1
$ hg ci -Aqm0
$ hg up null -q
$ echo c1 > f1 # backport
$ hg ci -Aqm1
$ hg mv f1 f2
$ hg ci -qm2
$ hg up 0 -q
$ hg merge 1 -q --tool internal:local
$ hg ci -qm3
$ hg merge 2
merging f1 and f2 to f2
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cat f2
c0
$ cd ..
Check for issue2089
$ hg init repo2089
$ cd repo2089
$ echo c0 > f1
$ hg ci -Aqm0
$ hg up null -q
$ echo c1 > f1
$ hg ci -Aqm1
$ hg up 0 -q
$ hg merge 1 -q --tool internal:local
$ echo c2 > f1
$ hg ci -qm2
$ hg up 1 -q
$ hg mv f1 f2
$ hg ci -Aqm3
$ hg up 2 -q
$ hg merge 3
merging f1 and f2 to f2
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ cat f2
c2
$ cd ..
Check for issue3074
$ hg init repo3074
$ cd repo3074
$ echo foo > file
$ hg add file
$ hg commit -m "added file"
$ hg mv file newfile
$ hg commit -m "renamed file"
$ hg update 0
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg rm file
$ hg commit -m "deleted file"
created new head
$ hg merge --debug
searching for copies back to rev 1
unmatched files in other:
newfile
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'file' -> dst: 'newfile' %
checking for directory renames
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: 19d7f95df299, local: 0084274f6b67+, remote: 5d32493049f0
note: possible conflict - file was deleted and renamed to:
newfile
newfile: remote created -> g
getting newfile
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg status
M newfile
$ cd ..